Washing machine and method of controlling the same

ABSTRACT

A washing machine and method of controlling the washing machine. The washing machine includes a fixed tub, a rotating tub, a detergent dispenser and a control unit. The detergent dispenser contains a detergent, receives a preset quantity of washing water and allows the detergent to be dissolved therein, thus forming a liquid detergent. The control unit controls the liquid detergent contained in the detergent dispenser to be sprayed on laundry in the rotating tub after a completion of direct supplying of a large amount of the washing water to one or more of the fixed tub and the rotating tub.

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims the benefit of Korean Application No. 2002-41967, filed Jul. 18, 2002, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates generally to a washing machine and method of controlling the same, and more particularly, to a washing machine and method of controlling the same, which dissolves a detergent using a detergent dispenser and supplies the dissolved liquid detergent to a washing tub.

[0004] 2. Description of the Related Art

[0005] In general, washing machines are divided into drum-type washing machines and washing machines using pulsators. The drum-type washing machine washes laundry by a displacement of the laundry caused by a rotation of a rotating tub, while the washing machine using the pulsator washes the laundry by water currents generated by a rotation of the pulsator mounted on a bottom surface of a tub. Since the drum-type washing machine washes the laundry by the displacement caused by the rotation of the rotating tub, a small quantity of washing water to soak the laundry is used. This is one of advantages of the drum-type washing machine. Since the washing machine using the pulsator has to generate strong water currents by rotating the pulsator after supplying sufficient washing water for the laundry to be completely submerged under the washing water, a large quantity of washing water is needed in comparison with the drum-type washing machine.

[0006]FIG. 1 is a perspective view illustrating a construction of a conventional drum-type washing machine. As shown in FIG. 1, a fixed tub 102 is mounted in a body 100 to contain washing water therein, and a rotating tub 108 is mounted in the fixed tub 102 to perform washing, rinsing and spin-drying processes by a rotation of a motor 110. A number of holes are formed in a surface of the rotating tub 108, so the washing water can flow from the rotating tub 108 to the fixed tub 102 and vice versa through the holes and washing the water centrifugally separated from the laundry flows into a space between the rotating tub 108 and the fixed tub 102 during the spin-drying process. A washing machine provided with a drying heater 114 drying the laundry can further perform a drying process in addition to the washing, rinsing, and spin-drying processes of a general drum-type washing machine. In FIG. 1, hot and cold washing water passed through water supply valves 118 and 120 are first supplied by water pipes 124 to a detergent dispenser 122 and then supplied to the fixed tub 102 through a water supply pipe 126 along with a detergent.

[0007]FIG. 2 is a flowchart showing a method of controlling the conventional drum-type washing machine. As shown in FIG. 2, a washing course is set by a user at operation S202, and washing water of a quantity corresponding to the set washing course is supplied to the fixed tub 102 through the detergent dispenser 122 at operation S204. A detergent contained in the detergent dispenser 122 is dissolved by the washing water and supplied to the fixed tub 102 along with the washing water. After the washing water of the quantity corresponding to the set washing course has been supplied, a washing process is performed by the rotation of the rotating tub 108 at operation S206. After the washing process has been completed, a rinsing process is performed by repeating the supplying of a preset quantity of the washing water and spin-drying at operation S208. After the rinsing process has been completed, a spin-drying process is performed by the rotation of the rotating tub 108 at operation S210. After the spin-drying process has been completed, a drying process that removes the washing water soaked in the laundry in the rotating tub 108 is performed by operating the drying heater 114 at operation S212.

[0008] In the conventional drum-type washing machine, the washing water supplied to the detergent dispenser 122 is supplied to the fixed tub 102 through the detergent dispenser 122. In a course of supplying the washing water, the detergent contained in the detergent dispenser 122 is dissolved and supplied to the fixed tub 102 along with the washing water. In this case, since the washing water passes through the detergent dispenser 122 at a high speed, the detergent is supplied to the fixed tub 102 along with the washing water with the detergent insufficiently dissolved. The detergent needs to be sufficiently dissolved to prevent stains generated by an undissolved detergent from remaining on the laundry, and to improve a washing efficiency. Accordingly, after the supplying of the washing water and the detergent is completed, the detergent needs to be sufficiently diluted with the washing water by a forward rotation and a reverse rotation of the rotating tub 108 in the drum-type washing machine.

[0009] To sufficiently dilute the undissolved detergent in the rotating tub 108 with the washing water, a larger quantity of the washing water than a normal quantity of the washing water is needed. Although the drum-type washing machine is designed to wash the laundry with a small quantity of the washing water to soak the laundry, the larger quantity of the washing water than the normal quantity of the washing water has to be supplied to sufficiently dissolve the detergent because of the detergent sinking to a bottom of the fixed tub 102 which has to be dissolved using water currents generated by the forward rotation and the reverse rotation of the rotating tub 108. Thus, the quantity of the washing water is unavoidably increased to be equal to or greater than a maximum quantity of the washing water to soak the laundry in the conventional drum-type washing machine, so an increase in the quantity of the washing water causes an excessive consumption of the washing water, an increase in an amount of load on a rotating tub driving motor, and increases a time and energy required to heat the washing water in the drum-type washing machine in which a boiling process is carried out, thus increasing a power consumption and a total operating time thereof.

SUMMARY OF THE INVENTION

[0010] Accordingly, an aspect of the present invention is to provide a washing machine and method of controlling the washing machine, in which a large quantity of washing water is directly supplied to a rotating tub, a small quantity of the washing water to dissolve detergent is supplied to a detergent dispenser separately from the directly supplied washing water to allow the detergent to be dissolved at a high concentration in the detergent dispenser, and the dissolved high concentration liquid detergent is supplied to the rotating tub after the directly supplied washing water has been supplied to the rotating tub so that the laundry is sufficiently soaked in the washing water.

[0011] Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

[0012] To accomplish the above and/or other aspects, a washing machine having a fixed tub and a rotating tub, comprising a detergent dispenser containing a detergent, receiving a preset quantity of washing water and allowing the detergent to be dissolved therein, thus forming a liquid detergent; and a control unit controlling the liquid detergent contained in the detergent dispenser to be sprayed on laundry in the rotating tub after a completion of direct supplying of a large amount of the washing water to the fixed tub.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] These and other aspects and advantages of the invention will become apparent and more readily appreciated from the following description of the preferred embodiments, taken in conjunction with the accompanying drawings of which:

[0014]FIG. 1 is a perspective view illustrating a construction of a conventional drum-type washing machine;

[0015]FIG. 2 is a flowchart illustrating a conventional method of controlling the conventional drum-type washing machine;

[0016]FIG. 3 is a perspective view illustrating a construction of a drum-type washing machine in accordance with an embodiment of the present invention;

[0017]FIG. 4 is a block diagram illustrating the drum-type washing machine of FIG. 3; and

[0018]FIG. 5 is a flowchart illustrating a method of controlling the drum-type washing machine of FIG. 3.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Reference will now made in detail to the present preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. The embodiments are described below in order to explain the present invention by referring to the figures.

[0020] Referring to FIGS. 3 to 5, a washing machine and control method thereof is described. FIG. 3 is a perspective view illustrating a construction of a drum-type washing machine in accordance with an embodiment of the present invention. As shown in FIG. 3, a fixed tub 302 is mounted in a body 300 to contain washing water, and a rotating tub 308 is mounted in the fixed tub 302 to perform washing, rinsing, and spin-drying processes while being rotated by a driving force of a motor 310. A number of holes are formed in the rotating tub 308, so that the washing water can flow from the rotating tub 308 to the fixed tub 302 and vice versa and the washing water centrifugally separated from laundry flows into a space between the rotating tub 308 and the fixed tub 302 during a spin-drying process. The washing machine may be provided with a drying heater 314 drying the laundry. The drying heater performs a drying process in addition to the washing, rinsing, and spin-drying processes of a drum-type washing machine. Further, the drum-type washing machine provided with a washing water heating unit 330 can provide a same effect as that of directly boiling the laundry by heating the washing water to a high temperature. A large part of the washing water supplied through a first water supply valve 318 and a second water supply valve 320 is directly supplied to the fixed tub 302 through water supply pipes 328. A remaining small part of the washing water supplied through the first and second water supply valves 318 and 320 is supplied to a detergent dispenser 322 through the water supply pipes 324 and used to dissolve the detergent contained in the detergent dispenser 322. The liquid detergent dissolved by the remaining small part of the washing water in the detergent dispenser is supplied to the fixed tub 302 by a water pipe 328 that is connected between the detergent dispenser 322 and the fixed tub 302 after a completion of the direct supplying of the large part of the washing water.

[0021] In the washing machine, the small part of the washing water containing the detergent is sprayed on the laundry in the rotating tub 308, so that the large part of the washing water is uniformly supplied to the laundry, as a whole. After the direct supplying of the large part of the washing water is completed, the liquid detergent, which is supplied from the detergent dispenser 322 to the fixed tub 302, is sprayed on the laundry, so that the liquid detergent is uniformly supplied to the whole laundry.

[0022] In the washing machine a sum of a quantity of the washing water directly supplied to the fixed tub 302 and a quantity of the washing water supplied to the detergent dispenser 322 is less than or equal to a quantity of the washing water corresponding to a washing course set by a user. For example, when the quantity of the washing water corresponding to the set washing course is 10 liters, the sum of the quantity of the washing water supplied to the fixed tub 302 and the quantity of the washing water supplied to the detergent dispenser 322 is less than or equal to 10 liters. This restriction prevents a total quantity of the washing water from increasing as a result of an addition of the quantity of the washing water to dissolve the detergent to the quantity of washing water corresponding to the set washing course. Accordingly, an increase in the total quantity of the washing water is suppressible.

[0023]FIG. 3 shows the construction of a drum-type washing machine of an embodiment of the present invention. However, it is understood by those of skill in the art that the above-described construction can be applied to general washing machines using pulsators.

[0024]FIG. 4 is a block diagram illustrating the drum-type washing machine FIG. 3. As shown in FIG. 4, a control unit 402 controls an overall operation of the washing machine, such as washing, rinsing, spin-drying, and drying processes. An input unit 406 sets washing conditions desired by a user, or selectively commands only processes needed by a user. The washing conditions and commands set by the input unit 406 are transmitted to the control unit 402. A water level sensor 404 is used to detect a quantity of washing water supplied, and detects the quantity of the washing water supplied to the fixed tub 302 and provides information about the detected quantity of the washing water to the control unit 402.

[0025] A drive unit 410 drives the motor 310, a drain pump 316, the drying heater 314, a display unit 412, the first and second water supply valves 318 and 320 and the like. The motor 310 periodically rotates the rotating tub 308 in forward and reverse directions at a high speed during washing or rinsing processes, and rotates the rotating tub 308 in a forward direction at the high speed during a spin-drying process. The drain pump 316 discharges the washing water stagnating on a bottom surface of the fixed tub 302. The drying heater 314 dries the laundry by circulating heated air through the fixed tub 302. The display unit 412 visually displays an operating state of the drum-type washing machine. The first and second water supply valves 318 and 320 control the supplying of hot and cold water, respectively.

[0026] Referring to FIG. 5, a method of controlling the drum-type washing machine FIG. 3 is described. FIG. 5 is a flowchart illustrating the drum-type washing machine control method. As shown in FIG. 5, if a washing course is set by a user at operation S502, a preset small quantity of the washing water is supplied to the detergent dispenser 322 through the first and second water supply valves 318 and 320, and the detergent contained in the detergent dispenser 322 is dissolved at operation S504 a. Simultaneously, the washing water of a quantity obtained by subtracting the preset small quantity of the washing water supplied to the detergent dispenser 322 from a total quantity of the washing water corresponding to the washing course set by the user is directly supplied to the fixed tub 302 through the water supply pipes 328 and sprayed on the laundry at operation S504 b. Accordingly, the laundry can be uniformly soaked by spraying a large part of washing water thereon.

[0027] After the supplying of the large part of the washing water to the fixed tub 302 is completed, a high concentration liquid detergent dissolved by the washing water in the detergent dispenser 322 is sprayed on the sufficiently soaked laundry on which the large part of the washing water has been sprayed at operation S506. Since the sufficiently dissolved liquid detergent is sprayed on the laundry after the large part of the washing water has been supplied to the laundry and then the laundry has been sufficiently soaked, a generation of stains on the laundry, which may be generated by the detergent when an insufficiently dissolved detergent is supplied to the laundry that is insufficiently soaked, is preventable. Further, since the detergent can be dissolved by the small quantity of the washing water, the total quantity of the washing water is decreased in comparison with a case where the total quantity of the washing water and the detergent have been supplied together and then the detergent is dissolved in the fixed tub 302. Therefore, a quantity of used washing water can be decreased. Further, since the previously dissolved detergent is supplied to the fixed tub 302, the undissolved detergent does not remain, so the washing performance of the washing machine is maximized.

[0028] After the supplying of the washing water and the liquid detergent is completed, the washing process is performed by rotating the rotating tub 308 at operation S508. Thereafter, the rinsing process is performed by repeating the supplying of the washing water and spin-drying at operation S510. Thereafter, the spin-drying process is performed by rotating the rotating tub 308 at operation S512. After the spin-drying process is completed, the drying process that removes the water soaked in the laundry in the rotating tub 308 is performed by operating the drying heater 314 at operation S514.

[0029] The drum-type washing machine is constructed so that a large part of washing water is directly supplied to the fixed and rotating tubs without passing through a detergent dispenser, and a small part of the washing water to dissolve a detergent is supplied to the detergent dispenser separately from the large part of the washing water to dissolve the detergent at a high concentration in the detergent dispenser. With this construction, stains, which may be generated by an undissolved detergent remaining on laundry, are preventable and a washing performance of the drum-type washing machine can be improved by sufficiently spraying the high concentration liquid detergent on the laundry after the large part of the washing water is supplied to the fixed tub. Further, since the previously dissolved detergent is supplied, a total quantity of the washing water can be greatly decreased in comparison with a case where the washing water and the detergent are supplied together, and a power consumption and a total time required to wash the laundry are decreased by a reduction in an amount of load on the rotating tub driving motor. Further, since the total quantity of the washing water is decreased, a time required to heat the washing water is greatly decreased in washing machines that perform a boiling process by heating the washing water.

[0030] Although a few preferred embodiments of the present invention have been shown and described, it would be appreciated by those skilled in the art that changes may be made in this embodiment without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents. 

What is claimed is:
 1. A washing machine having a fixed tub and a rotating tub, comprising: a detergent dispenser containing a detergent, receiving a smaller part of washing water, and allowing the detergent to be dissolved therein to form a liquid detergent; and a control unit controlling the liquid detergent contained in the detergent dispenser to be sprayed on laundry in the rotating tub after a larger part of the washing water is directly supplied to one or more of the fixed tub and the rotating tub.
 2. The washing machine according to claim 1, further comprising: a first supply path directly supplying the larger part of the washing water to one or more of the fixed tub and the rotating tub; and a second supply path supplying the smaller part of the washing water to the detergent dispenser, the first and second supply paths being separately formed.
 3. The washing machine according to claim 1, wherein the control unit controls the smaller part of the washing water to be supplied to the detergent dispenser to dissolve the detergent while the larger part of the washing water is directly supplied to one or more of the fixed tub and the rotating tub.
 4. The washing machine according to claim 1, wherein the control unit controls the liquid detergent contained in the detergent dispenser to be supplied to one or more of the fixed tub and the rotating tub to which the larger part of the washing water has been directly supplied.
 5. The washing machine according to claim 1, wherein a sum of a first quantity of the washing water supplied to the detergent dispenser and a second quantity of the washing water directly supplied to one or more of the fixed tub and the rotating tub is less than or equal to a respective quantity of the washing water corresponding to a washing course set by a user.
 6. The washing machine according to claim 1, wherein the washing machine is a drum-type washing machine having a washing water heating unit.
 7. A method of controlling a washing machine having a rotating tub, comprising: when a washing course is set, supplying washing water corresponding to the set washing course, forming a liquid detergent by dissolving a detergent contained in a detergent dispenser, and supplying the washing water of a quantity corresponding to the set washing course to the rotating tub; after the supplying of the washing water to the rotating tub is completed, spraying and supplying the liquid detergent to the rotating tub; and after the spraying of the liquid detergent is completed, performing washing, rinsing, and spin-drying processes.
 8. The method according to claim 7, wherein the detergent is dissolved by supplying a first quantity of the washing water to the detergent dispenser while a second quantity of the washing water is directly supplied to the rotating tub.
 9. The method according to claim 8, wherein a sum of the first quantity of the washing water supplied to the detergent dispenser and the second quantity of the washing water directly supplied to the rotating tub is less than or equal to the quantity of the washing water corresponding to the set washing course set by a user.
 10. The method according to claim 7, wherein the washing machine is a drum-type washing machine.
 11. A washing machine having a tub and a detergent dispenser therein, the detergent dispenser being provided with detergent, comprising: a control unit controlling a first quantity of washing water to dissolve the detergent forming liquid detergent to be applied to laundry in the tub and a second quantity of the washing water which is directly supplied to the tub, the liquid detergent and the second quantity of the washing water being provided in separate operations.
 12. The washing machine according to claim 11, further comprising: a first supply path supplying the first quantity of the washing water to the detergent dispenser; and a second supply path directly supplying the second quantity of the washing water to the tub, the first and second supply paths being separately formed.
 13. The washing machine according to claim 11, wherein the control unit controls the liquid detergent contained in the detergent dispenser to be supplied to the tub to which the second quantity of the washing water has been directly supplied.
 14. The washing machine according to claim 11, wherein a sum of the first quantity of the washing water supplied to the detergent dispenser and the second quantity of the washing water directly supplied to the tub is less than or equal to a respective quantity of the washing water corresponding to a washing course set by a user.
 15. The washing machine according to claim 11, wherein the washing machine is a drum-type washing machine.
 16. The washing machine according to claim 11, further comprising: a washing water heating unit to heat the washing water prior to the supplying of the washing water to the tub.
 17. The washing machine according to claim 11, further comprising: a water level sensor to detect a quantity of the washing water supplied to the tub and to communicate the detected quantity of the washing water to the control unit.
 18. The washing machine according to claim 11, wherein the first quantity of the washing water is less than the second quantity of the washing water.
 19. The washing machine according to claim 11, wherein the first quantity of the washing water is a preset quantity.
 20. The washing machine according to claim 11, wherein the second quantity of the washing water soaks the laundry in the tub prior to the liquid detergent being applied to the laundry.
 21. A method of operating a washing machine having a tub and a detergent dispenser therein, the detergent dispenser being provided with detergent, comprising: controlling a first quantity of washing water to dissolve the detergent to form liquid detergent to be applied to the tub and a second quantity of the washing water which is directly supplied to the tub, the liquid detergent and second quantity of washing water being provided to the tub in separate operations.
 22. The method according to claim 21, further comprising: supplying the first quantity of the washing water to the detergent dispenser while the second quantity of the washing water is directly supplied to the tub.
 23. The method according to claim 21, further comprising: prior to the controlling, determining both the first quantity of the washing water and the second quantity of the washing water corresponding to a set washing course.
 24. The method according to claim 23, wherein the determining comprises: calculating a sum of the first quantity of the washing water supplied to the detergent dispenser and the second quantity of the washing water directly supplied to the tub, which is less than or equal to a quantity of the washing water corresponding to the set washing course.
 25. The method according to claim 21, wherein the washing machine is a drum-type washing machine.
 26. The method according to claim 21, further comprising: heating the washing water prior to the supplying of the washing water to the tub.
 27. The method according to claim 21, further comprising: detecting a quantity of the washing water supplied to the tub; and communicating the detected quantity of the washing water so as to control the quantity of the washing water supplied.
 28. The method according to claim 21, wherein the first quantity of the washing water is less than the second quantity of the washing water.
 29. The method according to claim 21, wherein the first quantity of the washing water is a preset quantity.
 30. The method according to claim 21, further comprising: soaking the laundry in the tub by the second quantity of the washing water prior to the liquid detergent being applied to the laundry.
 31. A method of operating a washing machine having a tub and a detergent dispenser therein, the detergent dispenser being provided with detergent, comprising: controlling a first quantity of washing water to dissolve the detergent to form liquid detergent and a second quantity of the washing water which is directly supplied to the tub; and applying the liquid detergent to laundry in the tub after the second quantity of the washing water is directly supplied to the tub.
 32. A method of operating a washing machine having a tub and a detergent dispenser therein, the detergent dispenser being provided with detergent, comprising: supplying a first washing water to the detergent dispenser; dissolving detergent in the first washing water to form liquid detergent; supplying a second washing water directly to the tub; and supplying the liquid detergent to the tub in a separate operation from the supplying of the second washing water.
 33. A method of controlling a washing machine having a tub therein, comprising: setting a washing course; determining a first portion of watering water and a second portion of the washing water corresponding to the set washing course; forming liquid detergent by dissolving detergent by the first portion of the washing water; supplying the second portion of the washing water directly to the tub; after the supplying of the second portion of the washing water to the tub, spraying liquid detergent into the tub; and performing washing, rinsing, and spin-drying operations after the spraying.
 34. A method of operating a washing machine having a tub, a detergent dispenser, and first and second water supply valves therein, the detergent dispenser being provided with detergent, comprising: first controlling a supply of water to the tub by opening or closing a first water supply valve; and second controlling a supply of the water to the detergent dispenser by opening or closing a second water supply valve, wherein the first controlling provides a first quantity of the water to dissolve the detergent forming liquid detergent to be applied to laundry in the tub and the second controlling provides a second quantity of the water to be directly supplied to the tub prior to applying the liquid detergent.
 35. A washing machine having a tub and a detergent dispenser therein, the detergent dispenser being provided with the detergent and receiving a first quantity of washing water to allow the detergent to be dissolved in the first quantity of the washing water to form liquid detergent to be applied to laundry in the tub, comprising: a control unit controlling the liquid detergent applied to the laundry in the tub, after the first quantity of the washing water is directly supplied to the tub.
 36. A washing machine having a tub and a detergent dispenser therein, the detergent dispenser being provided with detergent, comprising: a control unit; one or more first water supply pipes directly supplying water from outside the washing machine to the tub; one or more second water supply pipes supplying water to the detergent dispenser; a first water supply valve opening and closing the one or more first water supply pipes; a second water supply valve opening and closing the one or more second water supply pipes, and the control unit controlling the first water supply valve to supply a first quantity of water to dissolve the detergent forming liquid detergent to be applied to laundry in the tub and the second water supply valve to directly supply a second quantity of the water to the tub. 